Tangential Air Separator And Flow Balancer For A Closed Fuel Circulation System

ABSTRACT

A combination air eliminator and flow balancer for a fluid circulation system includes a tank having a supply inlet, a supply outlet, a return inlet and a return outlet. The tank defines an interior having a vertical cylindrical configuration. The supply inlet is located above the supply outlet, the return inlet and the return outlet. The supply inlet introduces fluid into an upper portion of the interior of the tank in a tangential direction to induce rotational downward flow between the supply inlet and the supply outlet, which separates air contained within the fluid. The air migrates upwardly within the tank interior and is vented. The tank is capable of balancing flow by 1) returning fluid from the supply inlet to the return outlet without passing through the supply outlet, and 2) returning fluid from the return inlet to the supply inlet without passing through the return outlet,

CROSS-REFERENCE TO RELATED APPLICATION

This application claims the benefit of U.S. Provisional Application No.62/107,784, filed Jan. 26, 2015.

BACKGROUND AND SUMMARY

This invention relates to a closed fluid circulation system, such as ahydronic heating system, and more particularly to a device foreliminating air from the fluid and for balancing the flow of fluid inthe system.

A closed fluid circulation system typically includes a pump thatcirculates fluid through a closed conduit arrangement. In a closedhydronic heating system, the pump circulates the fluid first through aboiler or other heating device, and the heated fluid is then supplied toradiators or other such devices for interior heating. The cool fluid isthen circulated back to the pump and again through the boiler forreheating.

It is known that air can become present in the fluid of hydronic heatingsystem, and it is desirable to eliminate the air in order to preservethe integrity of the fluid and to prevent pipe corrosion. Various typesof air elimination devices are known, and can be incorporated in thefluid circulation system.

It is also known that a flow imbalance can occur between the pump outputand the return flow of fluid that is supplied to the pump. That is,there can be times when return flow of fluid from the loads to the pumpis more than the pump intake can handle, as well as times when thereturn flow of fluid to the pump is less than the pump requires toprovide a desired pump output. To accommodate such a flow imbalance, itis known to provide a flow balancing tank that allows fluid to beshort-circuited back to the pump if pump output is more than can besupplied to the loads at a given time and it also allows fluid to bereturned to the loads without circulation through the pump if the returnflow of fluid from the loads is more than the pump intake canaccommodate.

Is an object of the present invention to provide a device that can beincorporated in a closed fluid circulation system and that is capable ofperforming both an air elimination function and a flow-balancingfunction.

In accordance with the present invention, a combination air eliminatorand flow balancer is provided, for a closed fluid circulation systemthat includes a circulation loop and a pump having an intake and outlet.Representatively, the closed fluid circulation system may be in the formof a hydronic heating system. The combination air eliminator and flowbalancer includes a tank positioned between the circulation loop and thepump intake and outlet. The tank includes a supply inlet that receivessupply fluid from the pump outlet and a supply outlet that suppliesfluid to the circulation loop. The tank further includes a return inletthat receives return fluid from the circulation loop and a return outletthat supplies fluid to the pump intake. The tank defines an interiorhaving a generally cylindrical configuration that extends along agenerally vertical axis, and the supply inlet of the tank is located atan elevation above the supply outlet, the return inlet and the returnoutlet. The supply inlet is positioned in a generally non-radialorientation such that fluid flow is introduced into an upper portion ofthe interior of the tank in a non-radial flow direction so as to inducerotational downward fluid flow between the supply inlet and the supplyoutlet, which induces separation of air contained within the fluid. Theair migrates upwardly within the interior of the tank, and an air ventinterconnected with the tank functions to exhaust air from the tankinterior to atmosphere. In addition, the tank is capable of balancingflow by 1) returning fluid from the supply inlet to the return outletwithout the fluid passing through the circulation loop, and 2) returningfluid from the return inlet to the supply inlet without the fluidpassing through the pump.

Representatively, the supply inlet may be located on the same side ofthe tank as the supply outlet, and may be configured so as to definefluid flow paths that are generally parallel to each other. The returninlet and the return outlet may be located on a side of the tankopposite that of the supply inlet and the supply outlet, and may beconfigured so as to define flow paths that are generally parallel toeach other. The return inlet and the return outlet may be configured soas to define flow paths that are generally in alignment with each other.The supply outlet, the return inlet and the return outlet may bepositioned at generally the same elevation below the supply inlet.

The present invention also contemplates a closed fluid circulationsystem and a method of circulating fluid in a closed fluid circulationsystem, substantially in accordance with the foregoing summary.

These, and other aspects and objects of the present invention will bebetter appreciated and understood when considered in conjunction withthe following description and the accompanying drawings. It should beunderstood, however, that the following description, while indicating arepresentative embodiment of the present invention, is given by way ofillustration and not of limitation. Many changes and modifications maybe made within the scope of the present invention without departing fromthe spirit thereof, and the invention includes all such modifications.

BRIEF DESCRIPTION OF THE DRAWINGS

A clear conception of the advantages and features constituting thepresent invention, and of the construction and operation of typicalmechanisms provided with the present invention, will become more readilyapparent by referring to the exemplary, and therefore non-limiting,embodiment illustrated in the drawings accompanying and forming a partof this specification, wherein like reference numerals designate thesame elements in the several views, and in which:

FIG. 1 is a schematic view of a closed fluid circulation systemincorporating the combination air eliminator and flow balancer inaccordance with the present invention;

FIG. 2 is a top plan view of the combination air eliminator and flowbalancer as shown in FIG. 1;

FIG. 3 is a section view taken along line 3-3 of FIG. 2;

FIG. 4 is a section view taken along line 4-4 of FIG. 2; and

FIG. 5 is a schematic view generally illustrating the manner in whichfluid flows through the combination air eliminator and flow balancer ofFIGS. 2-4.

In describing the embodiment of the invention which is illustrated inthe drawings, specific terminology will be resorted to for the sake ofclarity. However, it is not intended that the invention be limited tothe specific terms so selected and it is to be understood that eachspecific term includes all technical equivalents which operate in asimilar manner to accomplish a similar purpose. For example, the words“connected”, “attached”, or terms similar thereto are often used. Theyare not limited to direct connection but include connection throughother elements where such connection is recognized as being equivalentby those skilled in the art.

DETAILED DESCRIPTION

The present invention and the various features and advantageous detailsthereof are explained more fully with reference to the non-limitingembodiments described in detail in the following description.

FIG. 1 schematically illustrates a closed fluid circulation system,which representatively may be a hydronic heating system. In such asystem, a pump P circulates fluid, such as water, through a conduit suchas C1 to a boiler B, where the fluid is heated. The heated fluid is thensupplied through a supply conduit C2 to a combination air eliminator andflow balancer 10 constructed in accordance with the present invention,from which it is supplied through a supply conduit C3 from aireliminator and flow balancer 10 to a series of heating loads, such asradiators within various rooms or spaces of a building. The cool fluidis then returned to air eliminator and flow balancer 10 through a returnconduit C4, and returns to the intake of pump P through a return conduitC5. Air eliminator and flow balancer 10 includes a supply inletconnection 12. a supply outlet connection 14, a return inlet connection16 and a return outlet connection 18. In a manner as is known, supplyinlet connection 12 includes a flanged connection that is flow coupledto supply conduit C2, although it is understood that any othersatisfactory fluid flow connection may be employed. Similarly, supplyoutlet connection 14 is flow coupled to supply conduit C3, return inlet16 is flow coupled to return conduit C4, and return outlet C5 is flowcoupled to return conduit C5.

Air eliminator and flow balancer 10 includes a body in the form of ashell or tank 20, which includes a generally cylindrical side wall 22, atop wall 24 and a bottom wall 26, which cooperate to define an enclosedvolume in the interior of tank 20. In a manner as is known, tank 20 alsoincludes a series of legs 28 for supporting the air eliminator and flowbalancer 10 above a support surface, such as a floor.

Referring to FIGS. 1-3, supply inlet connection 12 is flow coupled tothe upstream end of a supply inlet conduit 30, the downstream end ofwhich is flow coupled to tank 20 through a supply inlet opening 32formed in tank side wall 22. On the same side of tank 20, supply outletconnection 14 is flow coupled to the downstream end of a supply outletconduit 34, the upstream end of which is flow coupled to tank 20 througha supply outlet opening 36 formed in tank side wall 22.

As also shown in FIGS. 1-3, return inlet connection 16 is flow coupledto the upstream end of a return inlet conduit 38, the downstream end ofwhich is flow coupled to tank 20 through a return inlet opening 40formed in tank side wall 22. On the same side of tank 20, return outletconnection 18 is flow coupled to the downstream end of a return outletconduit 42, the upstream end of which is flow coupled to tank 20 througha return outlet opening 44 formed in tank side wall 22. It can thus beappreciated that the supply inflow to and outflow from tank 20 throughsupply inlet opening 32 and supply outlet opening 36, respectively, arelocated on one side of tank 20, and that the return inflow to andoutflow from tank 20 through return inlet opening 40 and return outletopening 44 are on the opposite side of tank 20.

Referring to FIGS. 3 and 4, the interior of tank 20 is shown generallyat 50. Supply inlet opening 32 is located on tank side wall 22 so as tosupply fluid from supply inlet conduit 30 into the upper region of tankinterior 50. Supply outlet opening 36, on the other hand, is located ontank side wall 22 such that fluid flows outwardly from the tank interior50 from the lower region of tank interior 50.

Tank side wall 22 has a generally circular cross-section such that theboundary of tank interior 50 is generally circular. It is understood,however, that the boundary of tank interior 50 need not be perfectlycircular, and the tank interior 50 may also have a cross-section that isgenerally elliptical.

Supply inlet conduit 30 is oriented relative to tank interior 50 suchthat fluid flows into the tank interior 50 through supply inlet opening32 in a non-radial direction. That is. the path of fluid flow into thetank interior 50 is not aligned with a radius of the circlecircumscribed by tank side wall 22, but rather is generally parallel toa line that is tangential relative to the periphery of tank side wall 22(such flow being hereafter referred to as tangential flow). In a similarmanner, supply outlet conduit 34 is oriented relative to tank interior50 such that fluid flows out of the tank interior 50 through supplyoutlet opening 36 in a non-radial direction, to provide tangentialoutflow from tank interior 50 in the same manner as tangential inflow isprovided through supply inlet opening 32. The tangential fluid inflowthrough supply inlet conduit 30 is generally parallel to and above thetangential fluid outflow through supply outlet conduit 34.

Return inlet conduit 38 is oriented relative to tank interior 50 suchthat fluid flows into the tank interior 50 through return inlet opening40 in a non-radial direction, to provide tangential inflow to tankinterior 50 in the same manner as described above. Similarly, returnoutlet conduit 42 is oriented relative to tank interior 50 to providetangential outflow through return outlet opening 44. The flow paths ofreturn inlet conduit 38 and return outlet conduit 42 are also generallyparallel to each other. Representatively, in one embodiment asillustrated, the flow paths of return inlet conduit 38 and return outletconduit 42 are aligned with each other such that return inlet opening 40and return outlet opening 44 are in direct alignment with each other onopposite sides of tank interior 50.

Supply inlet conduit 30, supply outlet conduit 34, return inlet conduit38 and return outlet conduit 42 are oriented so as to provide fluid flowpaths that are generally parallel to each other. With this arrangement,the vertically offset parallel flow paths of supply inlet conduit 30 andsupply outlet conduit 34, which are located on one side of thecenterline of tank 20, are parallel to the flow paths of return inletconduit 38 and return outlet conduit 42, which are located on theopposite side of the centerline of tank 20. It is understood, however,that while generally parallel flow paths are shown and described, theflow paths may also be non-parallel and non-aligned so long as thegeneral arrangement, orientation and function of the supply and returnflow paths is maintained.

An air vent 52 is mounted to top wall 24 of tank 20 and a drain pipe 54is mounted to the bottom wall 26 of tank 20. Air vent 52 is constructedand arranged so as to enable air in the upper region of tank interior 52escape to atmosphere. Drain pipe 54 is employed to selectively empty thecontents of tank 20, such as for maintenance, replacement, cleaning,etc.

FIG. 5 schematically illustrates fluid flow through combination aireliminator and flow balancer 10 in operation. When pump P is operated,heated fluid from boiler B is supplied to supply inlet conduit 30 intothe upper region of tank interior 50. Due to the tangential orientationof supply inlet conduit 30 and the curved tank side wall 22, thetangential orientation of such heated fluid inflow causes the incomingfluid stream to circulate within the upper region of tank 20 in acircular manner. The incoming fluid stream then falls by gravity throughtank interior 52 create a somewhat downward spiraling flow of fluidwithin the tank interior 50. As the heated fluid continues to travelthrough tank interior 50 in a circular path in this manner, iteventually is discharged from tank interior 50 into supply outletconduit 34 for supply to the heating loads downstream therefrom. Afterthe heated fluid circulates through the heating loads and is cooled, thecool return fluid will is supplied to tank interior 50 through returninlet conduit 38, which as noted above is located in the lower region oftank interior 50 and may be at the same elevation as supply outletconduit 34. The cooled return fluid travels directly across the volumeof tank interior 50 into the return outlet conduit 42. A portion of suchfluid may circulate around the lower region of tank 50 before it passesinto return outlet conduit 42, but the majority of such fluid will passdirectly into the return outlet conduit 42 in a generally linear pathfrom return in the conduit 38. As can be appreciated, the cooled returnfluid generally stays in the lower region of tank interior 50 while thesupply fluid generally stays in the upper region of tank interior 50.

As the fluid travels a circular path around the tank interior 50,whether it be the heated fluid in the upper region of tank interior 50or the cooled fluid in the lower region tank interior 50, the circular,spiral flow of the fluid causes entrapped air contained within the fluidto migrate toward the center of tank interior 50. In FIG. 5, suchinwardly migrate entrapped air is represented by air bubbles shown at60. The entrapped air bubbles 60 migrate upwardly toward the top of tankinterior 50, where they can escape tank interior 50 through air vent 52.

In addition to the air separation function provided by the tangentialintroduction of fluid and the circular fluid flow path within tankinterior 50, tank interior 50 also is capable of providing a flowbalancing function if required. That is, tank interior 50 functions as abuffer between pump P and the heating loads. In the event the outputfrom pump P is greater than the loads downstream of tank 20 can accept,the fluid that cannot at that time be circulated to the loads cancirculate through the tank interior 50 and be discharged back to pump Pthrough return outlet conduit 42 without going through supply outletconduit 34 to the heating loads. The excess fluid is essentially shuntedback to the pump P to balance against incoming flow from the heatingloads. In a similar manner, in the event the output from the heatingloads is greater than the intake of pump P can accept, the fluid thatcannot at that time be circulated to the pump intake can circulatethrough the tank interior 50 and be discharged back to the heating loadsthrough supply outlet conduit 34 without going through return outletconduit 42 to the pump P. The excess fluid is essentially shunted backto the heating loads to balance against incoming flow from the pump P.While this condition is not ideal in that unheated fluid is beingsupplied to the heat loads, it is nonetheless desirable because amajority of the fluid in supply outlet conduit 34 is heated and becausethis flow balancing function enables pump P to operate in an efficientand optimal manner.

The present invention has been shown and described with the inlet andoutlet openings of the tank all being formed in the tank sidewall. Itshould be appreciated, however, that some or all of the inlet and outletopenings may also be formed in the upper and lower end walls of thetank. Other alternative configurations may be employed as desiredwithout departing from the essential air separation and flow balancingfunctions as set forth above.

Various additions, modifications and rearrangements are contemplated asbeing within the scope of the following claims, which particularly pointout and distinctly claim the subject matter regarded as the invention,and it is intended that the following claims cover all such additions,modifications and rearrangements.

I claim:
 1. A combination air eliminator and flow balancer for a closedfluid circulation system that includes a pump having an intake andoutlet and a circulation loop, comprising: a tank positioned between thecirculation loop and the pump intake and outlet, wherein the tankincludes a supply inlet that receives supply fluid from the pump outletand a supply outlet that supplies fluid to the circulation loop, andfurther includes a return inlet that receives return fluid from thecirculation loop and a return outlet that supplies fluid to the pumpintake, wherein the tank defines an interior having a generallycylindrical configuration that extends along a generally vertical axis,and wherein the supply inlet of the tank is located at an elevationabove the supply outlet, the return inlet and the return outlet, andwherein the supply inlet is positioned in a generally non-radialorientation such that fluid flow is introduced into an upper portion ofthe interior of the tank in a non-radial flow direction so as to inducerotational downward fluid flow between the supply inlet and the supplyoutlet, wherein the rotational downward fluid flow induces separation ofair contained within the fluid and wherein the air migrates upwardlywithin the interior of the tank, and further wherein the tank is capableof balancing flow by 1) returning fluid from the supply inlet to thereturn outlet without the fluid passing through the circulation loop,and 2) returning fluid from the return inlet to the supply inlet withoutthe fluid passing through the pump; and an air vent interconnected withthe tank for exhausting air from the tank interior to atmosphere.
 2. Thecombination air eliminator and flow balancer of claim 1, wherein thesupply inlet is located on the same side of the tank as the supplyoutlet.
 3. The combination air eliminator and flow balancer of claim 2,wherein supply inlet and the supply outlet are configured so as todefine fluid flow paths that are generally parallel to each other. 4.The combination air eliminator and flow balancer of claim 2, wherein thereturn inlet and the return outlet are located on a side of the tankopposite that of the supply inlet and the supply outlet.
 5. Thecombination air eliminator and flow balancer of claim 4, wherein thereturn inlet and the return outlet are configured so as to define flowpaths that are generally parallel to each other.
 6. The combination aireliminator and flow balancer of claim 5, wherein the return inlet andthe return outlet are configured so as to define flow paths that aregenerally in alignment with each other.
 7. The combination aireliminator and flow balancer of claim 5, wherein the supply outlet, thereturn inlet and the return outlet are at generally the same elevationbelow the supply inlet.
 8. The combination air eliminator and flowbalancer of claim 1, wherein the circulation loop comprises a hydronicheating system, and further comprising a fluid thing arrangementinterposed between the pump and the supply inlet.
 9. A closed fluidcirculation system, comprising: a circulation loop; a pump forcirculating fluid through the circulation loop, wherein the pumpincludes an intake and an outlet; and a combination air eliminator andflow balancer interconnected in the circulation loop, comprising a tankpositioned downstream of the pump outlet, wherein the tank includes asupply inlet that receives supply fluid from the pump outlet and asupply outlet that supplies fluid to the circulation loop, and furtherincludes a return inlet that receives return fluid from the circulationloop and a return outlet that supplies fluid to the pump intake, whereinthe tank defines an interior having a generally cylindricalconfiguration that extends along a generally vertical axis, and whereinthe supply inlet of the tank is located at an elevation above the supplyoutlet, the return inlet and the return outlet, and wherein the supplyinlet is positioned in a generally non-radial orientation such thatfluid flow is introduced into an upper portion of the interior of thetank in a non-radial flow direction so as to induce rotational downwardfluid flow between the supply inlet and the supply outlet, wherein therotational downward fluid flow induces separation of air containedwithin the fluid and wherein the air migrates upwardly within theinterior of the tank and wherein the tank includes an air vent forexhausting air from the tank interior to atmosphere, and further whereinthe tank is capable of balancing flow by 1) returning fluid from thesupply inlet to the return outlet without the fluid passing through thecirculation loop, and 2) returning fluid from the return inlet to thesupply inlet without the fluid passing through the pump.
 10. The closedfluid circulation system of claim 9, wherein the circulation loopcomprises a hydronic heating system.
 11. The closed fluid circulationsystem of claim 9, wherein the supply inlet is located on the same sideof the tank as the supply outlet.
 12. The closed fluid circulationsystem of claim 11, wherein the supply inlet and the supply outlet areconfigured so as to define fluid flow paths that are generally parallelto each other.
 13. The closed fluid circulation system of claim 11,wherein the return inlet and the return outlet are located on a side ofthe tank opposite that of the supply inlet and the supply outlet. 14.The closed fluid circulation system of claim 13, wherein the returninlet and the return outlet are configured so as to define flow pathsthat are generally parallel to each other.
 15. The closed fluidcirculation system of claim 14, wherein the return inlet and the returnoutlet are configured so as to define flow paths that are generally inalignment with each other.
 16. The closed fluid circulation system ofclaim 14, wherein the supply outlet, the return inlet and the returnoutlet are at generally the same elevation below the supply inlet.
 17. Amethod of circulating fluid in a closed fluid circulation system thatincludes a pump and a circulation loop, comprising the acts of:connecting a tank in the closed fluid circulation system, wherein thetank includes a supply inlet, a supply outlet, a return inlet and areturn outlet, wherein the tank defines an interior having a generallycylindrical configuration that extends along a generally vertical axis,and wherein the supply inlet is located at an elevation above the supplyoutlet, the return inlet and the return outlet; introducing fluidthrough the supply inlet in a generally non-radial orientation such thatfluid flow is introduced into an upper portion of the interior of thetank in a non-radial flow direction so as to induce rotational downwardfluid flow between the supply inlet and the supply outlet, wherein therotational downward fluid flow induces separation of air containedwithin the fluid and wherein the air migrates upwardly within theinterior of the tank; exhausting air from the tank interior toatmosphere; and selectively balancing flow in the fluid circulationsystem by 1) returning fluid from the supply inlet to the return outletwithout the fluid passing through the circulation loop, or 2) returningfluid from the return inlet to the supply inlet without the fluidpassing through the pump.
 18. The method of claim 17, wherein thecirculation loop comprises a hydronic heating system.
 19. The method ofclaim 17, wherein the supply inlet is located on the same side of thetank as the supply outlet.
 20. The method of claim 19, wherein thesupply inlet and the supply outlet are configured so as to define fluidflow paths that are generally parallel to each other.
 21. The method ofclaim 19, wherein the return inlet and the return outlet are located ona side of the tank opposite that of the supply inlet and the supplyoutlet.
 22. The method of claim 21, wherein the return inlet and thereturn outlet are configured so as to define flow paths that aregenerally in alignment with each other.
 23. The method of claim 17,wherein the supply outlet, the return inlet and the return outlet are atgenerally the same elevation below the supply inlet.